Question about Growatt AC IN

[sunshine_eggo]

I don't understand why you would want to add complexity to your system by getting a European unit and an auto transformer. Each component has loss thru it and just makes it more complex. Yes, I understand you get the max output from the unit on both legs but why not just spend the money to get a unit that is built for our system in North America. I don't see the rest of the world buying North American units and converting them into European units.

This is an extremely common approach. It's more often done with Victron's 230V units that offer more features/power than the 120V units because they have NO split phase models. The only way to get native split phase is to get parallel inverters, which is more expensive than 1 230V and an autotransformer. The transformer is typically very efficient. In most cases, the features gained by this approach may be justified when a comparable model isn't available in split phase, or is at a higher cost.

Split phase is something of a redheaded stepchild, and selection is limited compared to 230V. You don't see reverse conversions because there is already a 230V model available.

 

[Zwy]

I don't understand why you would want to add complexity to your system by getting a European unit and an auto transformer. Each component has loss thru it and just makes it more complex. Yes, I understand you get the max output from the unit on both legs but why not just spend the money to get a unit that is built for our system in North America. I don't see the rest of the world buying North American units and converting them into European units.

The reason many buy into it is because Signature Solar sells it this way and really is one of the only options they offer.

Is it the right way? That remains to be seen, give it some time and we shall see how it all holds up.

Now, the reason they sell this setup is for a few reasons. One, it can take in 450V from PV. But the SCC is limited to 6000w per 5000W LVM- ES. This is why you usually see 2 of these units in parallel, it allows 12Kw of PV max and 10Kw of inverter capacity. The 450V PV input rating is the big sell, this allows fewer PV wires from the array as more panels are put in series, plus the voltage drop to SCC is much less.

Second is cost, the 5000W LVM- ES with auto transformer is $1298 https://shop.signaturesolar.us/products/5kw-es-transformer-kit. Not bad for a setup with split phase in a single unit with 120V capability. This unit is also stackable, up to 6 units. For comparison, one other inverter SS offers is SPF 6kW DVM off-grid inverter https://shop.signaturesolar.us/products/6kw-48v-250vac-80a-off-grid-inverter-by-growatt It offers split phase 120/240 but is not stackable as it is a low frequency inverter. If you look at any of the inverters in the GW line at SS 5Kw and larger, you will find they are all low freq inverters and are not stackable. While these inverters will handle a large surge, it also limits the ability to expand a system down the line. The only stackable unit over 5Kw is the 5000W LVM-ES.

Other vendors out there do offer split phase 120/240V units that are stackable such as Watts247. These are high freq inverters. An example is the LV6548 from MPP Solar. However in the GW lineup, you will find only low freq inverters in the 5Kw and up range. If you want a high freq inverter with split phase 120/240V, you only have the choice of two 3Kw units is parallel.

When it comes to PV input max voltage, the only choices up to 450V is the 5000W LVM-ES. Most other units are 250V rated but have 2 SCC's built into the unit. This allows the same or more charging amps and PV is just more parallel strings compared to having more panels in series with the higher voltage. My thoughts are many buying the 5000W LVM-ES is the PV array is a long distance from the unit. But if distance isn't far, the better choice may be the lower voltage units with units in parallel.

There are some 450V PV rated units in split phase out there, such as the LVX 6048, https://watts247.com/product/lvx-6048-hybrid-solar-inverter-split-phase-120v-240v/ which might be a better choice for the original member posting as the auto transformer is built in and the Neutral issue would be handled in the unit. This unit is low freq, but is stackable. This is a nice unit.

 

[jsmalone1]

These units do not put out 120v they are 240v. From the AC in L1 goes to hot and L2 goes to neutral. Ground is ground. Be sure if using multiple units all of em have L1 to hot and L2 neutral. Not mixed up

I have 2 -5000 watt units. The input and output is 240 volt. There is no nuetral, period.

 

[Bleedingblue]

I have 2 -5000 watt units. The input and output is 240 volt. There is no nuetral, period.

Can you post a pic of you connection points? What units do you have? My dad has growatts and it's the exact same as mine. He has the 5000es models

 

[jsmalone1]

So 240 volt input w/ground (optional utility feed) & 240 volt output w/ ground. The transformer is wired into my panel being fed by my solar/ battery output to generate a neutral for 120 volt use in my home

 

[Tecnodave]

The real questions are:


1:> Is it listed by a NRTL (National Reliability Testing Laboratory) for use in the U.S.
2:> Has this installation been approved by the AHJ. (Authority Having Jurisdiction)? (i.e. the building department?)
3:> Is your insurance company aware of this installation?

If your answers are not a yes,yes,yes.....You are on your own if you have a system fail which may burn down your home or kill someone.
Your insurance probably will require “Listed by an NRTL to the revelant standard” such as “Listed by ETL to U.L. 1741”

Absolutely no system that is 230 volt single phase is listed by a NRTL to U.L. 1741,

The United States uses the 120/240 volt split phase system for safety......the hot wires are 120 volts to ground due to the fact that it is safer as almost all portable devices are 120 volts for safety and 120 volts is far less likely to kill you than 230 volts....

I have seen insurance companies walk away from this situation as they have in their requirements to be “Listed to U.L.” in their insurance “contract” ........yes it is a contract....ask any lawyer

When I purchased my 1928 house the insurance company would not insure me with a fuse panel even though it is legal as it was legal when installed and it is grandfathered and legal to the building inspector as it was legal when installed and there has never been an upgrade. Simply installing a modern split phase breaker panel made the insurance company happy even though I did not get a building department approval to upgrade from fuses to breakers.

I have removed quite a few 230 volt systems for real estate agents as they could not legally sell a home with a 230 volt single phase system even if it is equipped with an isolation transformer or an autotransformer.

Much simpler is to use a system “Listed by ETL to U.L. 1741” (stand alone) or “ Listed by ETL to U.L.1741SA” (grid tie)

My system is 120/240 split phase even though I do not have a 120/240 volt utility due to the fact that my inverter charger is “Listed by ETL to U.L. 1741“ as the MagnaSine MS4024AE main transformer IS an autotransformer and is tested to UL 1741 with a 120 volt input and 120/240 output.....

YES......it does output 120/240 split phase when in bypass mode...(Inverter not operating) with only 120 volts input...built that way.....tested that way.....listed that way....covered by my insurance

Why do I not get my utility upgraded......say $500,000 at the very minimum to bring the 120/240 to my rural property

Besides which the California PSPS......Public Power Supply Shutdown for safety when storm winds occur as our utility would rather reward shareholders than upgrade our 1930’s network. at times I will be out of utility power for weeks, one time it was 3 months before they restored my power

My utility calls themselves Pigs, Goats , and Elephants.......they got that right. Northern California PG&E

 

[Bleedingblue]

So 240 volt input w/ground (optional utility feed) & 240 volt output w/ ground. The transformer is wired into my panel being fed by my solar/ battery output to generate a neutral for 120 volt use in my home

As long as it is pumping out 120/120 to the panel you are good.
Be prepared for vast amounts of hate and vitrol on what you should do according to someone else.
I've been running these single phase inverters for over a year and they have been excellent.

One thing I would do is put tape on the wires so you know which one is which.

 

[robby]

The real questions are:


1:> Is it listed by a NRTL (National Reliability Testing Laboratory) for use in the U.S.
2:> Has this installation been approved by the AHJ. (Authority Having Jurisdiction)? (i.e. the building department?)
3:> Is your insurance company aware of this installation?

If your answers are not a yes,yes,yes.....You are on your own if you have a system fail which may burn down your home or kill someone.
Your insurance probably will require “Listed by an NRTL to the revelant standard” such as “Listed by ETL to U.L. 1741”

Absolutely no system that is 230 volt single phase is listed by a NRTL to U.L. 1741,

The United States uses the 120/240 volt split phase system for safety......the hot wires are 120 volts to ground due to the fact that it is safer as almost all portable devices are 120 volts for safety and 120 volts is far less likely to kill you than 230 volts....

I have seen insurance companies walk away from this situation as they have in their requirements to be “Listed to U.L.” in their insurance “contract” ........yes it is a contract....ask any lawyer

When I purchased my 1928 house the insurance company would not insure me with a fuse panel even though it is legal as it was legal when installed and it is grandfathered and legal to the building inspector as it was legal when installed and there has never been an upgrade. Simply installing a modern split phase breaker panel made the insurance company happy even though I did not get a building department approval to upgrade from fuses to breakers.

I have removed quite a few 230 volt systems for real estate agents as they could not legally sell a home with a 230 volt single phase system even if it is equipped with an isolation transformer or an autotransformer.

Much simpler is to use a system “Listed by ETL to U.L. 1741” (stand alone) or “ Listed by ETL to U.L.1741SA” (grid tie)

My system is 120/240 split phase even though I do not have a 120/240 volt utility due to the fact that my inverter charger is “Listed by ETL to U.L. 1741“ as the MagnaSine MS4024AE main transformer IS an autotransformer and is tested to UL 1741 with a 120 volt input and 120/240 output.....

YES......it does output 120/240 split phase when in bypass mode...(Inverter not operating) with only 120 volts input...built that way.....tested that way.....listed that way....covered by my insurance

Why do I not get my utility upgraded......say $500,000 at the very minimum to bring the 120/240 to my rural property

Besides which the California PSPS......Public Power Supply Shutdown for safety when storm winds occur as our utility would rather reward shareholders than upgrade our 1930’s network. at times I will be out of utility power for weeks, one time it was 3 months before they restored my power

My utility calls themselves Pigs, Goats , and Elephants.......they got that right. Northern California PG&E

It's the insurance issue that may make you cry. Even if you sneak past all the other issues and you somehow do get insurance or already have it. It won't matter if any form of electrical fire burns down or damages your house. Once the fire dept does the forensic work and finds that non compliant inverter system in the ashes it gives the insurance company an instant excuse not to pay out the claim or at the least tie you up in court. From what I have been told plugging in a non UL compliant device in an outlet is covered by insurance if it catches fire but running your electrical generation from a non compliant device is where you can run into problems. Worst yet if it was not certified by your local inspector or reported to the insurance company. That gives them a leg up in court.

 

[Tecnodave]

Robby,

You nailed it, that is exactly my point.

 

[Tecnodave]

But let me add to that, all appliances plugged into your house “must be listed to U.L. XXXX by XXXX (listing company)”
Lamps, hair dryers, vacuums, etc....

 

[jsmalone1]

Wow, the irony

 

[SolarPrep]

Let me remind all that it is becoming common practice now to subpoena on line activity, and other records to establish/clarify/defend/prosecute,

For example, if you buy a Victron/Growatt/choose your poison device in 230 volt, and hook it up, and something goes wrong, your "records" and comments are fair game in court. I think it was unfair to suggest that "hate" is at work here because Technodave or others are suggesting caution, or to buy UL approved devices. You might be in a position someday where some prosecutor asks you why you didn't heed his advice.

Why haven't more US companies stepped up to the plate, and brought out products that we desire? In a country the size of the US, and with the amount of wealth here, what is the excuse for being behind in technology to Europe and Asia? Oh, did I just open a can of worms?

 

[Zwy]

But let me add to that, all appliances plugged into your house “must be listed to U.L. XXXX by XXXX (listing company)”
Lamps, hair dryers, vacuums, etc....

What about TUVus Rhineland certification? Many are not aware of this certification. https://www.tuv.com/usa/en/ctuvus-certification.html

TUVus is UL1741 compliant according to this information.

Some of the inverters in the MPP Solar lineup are TUVus rated. The LVX6048 and LV6548 are examples. I did not see any Growatt inverter that meets this standard or UL1741 compliant.

 

[tangle]

Maybe an isolation transformer. But I shouldn't have to use one in the first place if I was indeed sold the USA model...

Oh, this frustrates me as it's already installed.

Just happened to me. I sent the new on in because it would not output 120 V on each leg. They sent me a replacement (yep a used one) and it did the same thing. I them test the voltage across not legs and it showed 240 V. I ordered the USA model also.

 

[Struc]

Just happened to me. I sent the new on in because it would not output 120 V on each leg. They sent me a replacement (yep a used one) and it did the same thing. I them test the voltage across not legs and it showed 240 V. I ordered the USA model also.

Are you talking about the SPF5000ES, or some other inverter? The SPF5000ES is a 240v only inverter.

 

[tangle]

Are you talking about the SPF5000ES, or some other inverter? The SPF5000ES is a 240v only inverter.

Yes, after some more reading, I noticed that. I figured that since is was the US model the 240 would have been like the US.

 

[Tecnodave]

Yes, after some more reading, I noticed that. I figured that since is was the US model the 240 would have been like the US.

If it states 240 volts and the input connectors are N and L1 it is not an american model, It is desidned for the european/asian market which is 240 volts single phase.

USA models are listed as 120/240 volts split phase and the input terminals are marked as L1 , N , and L2

European models cannot be listed as .......” Listed to U.L. 1741 by a US OSHA NRTL such as UL, ETL etc.

These are not safe to use in the U.S. or in any split phase service

Lack of the “Listed to U.L. 1741” label invalidates your insurance......if someone dies, its on you!

 

[tangle]

If it states 240 volts and the input connectors are N and L1 it is not an american model, It is desidned for the european/asian market which is 240 volts single phase.

USA models are listed as 120/240 volts split phase and the input terminals are marked as L1 , N , and L2

European models cannot be listed as .......” Listed to U.L. 1741 by a US OSHA NRTL such as UL, ETL etc.

These are not safe to use in the U.S. or in any split phase service

Lack of the “Listed to U.L. 1741” label invalidates your insurance......if someone dies, its on you!

They claim that the US model is safe for the US. The one I have is not split phase. It read 240 V AC across L and N. When L or N is read across ground it reads 0 V AC. So are you saying that the US model should read 120 V AC on both L and N across ground? If so they sent me the wrong model.

I have been trying to get a call from their level 2 tech support and walk me through it and they will not call.

 

[Tecnodave]

They claim that the US model is safe for the US. The one I have is not split phase. It read 240 V AC across L and N. When L or N is read across ground it reads 0 V AC. So are you saying that the US model should read 120 V AC on both L and N across ground? If so they sent me the wrong model.

I have been trying to get a call from their level 2 tech support and walk me through it and they will not call.

The USA models will have 120 volts between L1 and N , 120 volts between L2 and N , and 240 volts between L1 and L2 , That is what is defined as split phase, the Neutral is halfway between L1 and L2, That is how we get 120 volts for lights, fans, etc, and 240 volts for water heaters, stoves, air conditioners, etc

In outer countries there is 240 volts only, lights, radios, and electric stoves are all 240 volts, there is no low voltage for small appliances

Absolutely no inverter that is rated 240 volts with only L1 and N connectors is safe for use in any split phase country, which includes U.S. , Canada, Mexico, US possessions incliding Puerto Rico and others , Antartica, a few South American countries.

Split phase does not appear in any of Asia or Europe, not sure about Africa


Asian and European inverters must be especially manufactured for the split phase market.

Victron is an European manufacturer that does make split phase american market inverters.

 

[sunshine_eggo]

Victron is an European manufacturer that does make split phase american market inverters.

No they don't. They make one version for the RV market that can pass through L2 if on split phase shore power or provide L1 to both legs of the RV panel if on single phase - targeted for "easy mode" permitting 50A RVs to freely connect to single or split phase power.

All of their other inverters are either 120VAC/60Hz or 230VAC/50Hz.

To get split phase out of Victron, you need 2X 120V units operating in parallel to provide 120/240VAC split phase OR one of their Euro models configured for 240VAC/60Hz coupled with an autotransformer to provide 120/240VAC.

To my knowledge, no Victron is UL1741 (or SA) listed. Some are UL 458 for marine/RV.